Conceptual model of spatial level structure for developing multi-functional parks to reduce urban flood risk: A case study in Ho Chi Minh city

Rapid urbanisation with unexpected reductions in permeable surfaces is considered to be a cause of increasing flood vulnerability in many cities worldwide, in parallel with the increasing demand for green spaces resulting from rising urban concentrations. The development of urban public parks, which are expected to contribute to water infiltration and storage for water absorption capacity by increasing green space and water area, is necessary in urban development planning to reduce flood risk. However, the increasing urban concentration resulting in the scarcity of land has become a significant challenge to this strategy, particularly in urban centres. Based on the literature review of some emerging theories of sponge city and flood resilience, and some early concept of vertical development for cities and parks, this paper presents a concept of a Model of Spatial Level Structure (MSLS) including three elevated levels for different groups of activities, with the aim of helping urban multi-function parks allocate more areas for green spaces and water storage on the ground level. With a case study of the 23–9 park in the city centre of Ho Chi Minh City, the application of this model shows evidence of an increase in area for greenspace development by 30%. This implies that urban parks should dedicate areas on the ground level for developing green spaces and water storage, by leveling up certain functional activities along with the vertical spatial development. The concept is expected to be useful for other public parks in other cities worldwide, particularly in mega-coastal cities facing a shortage of green spaces and water areas due to the uncontrolled rise in impermeable areas.